He started his career playing hockey in his hometown of Delisle, He and his brothers played for the senior Delisle Tigers.

From 1940 to 1947, his brother Max Bentley was his teammate and linemate in Chicago. Both brothers have been elected to the Hockey Hall of Fame, and in 1998, both brothers were named to List of 100 greatest hockey players by The Hockey News, Max at number 48 and Doug at number 73.
On March 13, 1966 in an Eastern Hockey League game vs Jacksonville, Doug Bentley inserted his son, Doug Jr. (b. June 1, 1951) into the game when the team was short of players due to injuries. Doug Jr. was only 14 years of age at the time, becoming the youngest player to play a shift in a professional hockey league.